Thanks in advance to anyone kind enough to answer: in re: T101
--if the manual lever is in the "on" position, does that mean the automatic functions are over-ridden and therefore the T101 is "out of the loop" until that switch is changed to the "off" position?
--can the T101 be functional (eg, being "on" for an hour every day) at the same time that my manual switch is functional (eg, available to be "on" for an hour here and there)?

Got to pick one or the other. Manual overrides the timer. The lever should offer manual or auto, right?

From the instruction sheet- TO OPERATE SWITCH MANUALLY: Move MANUAL LEVER
Below CLOCK-DIAL left or right as indicated by arrows. This
Will not effect next operation.

I have a T101 but it doest seem to keep the real time. If I set it today for the actual time it will kick on and kick off but the next day the actual time is off. So if I want the pool to go on everyday at noon, I will get noon the first day and then I get a different time every day unless I reset it.

You are either losing power to the timeclock motor, or the motor is defective, Shorting of internal windings I would think the clock to move faster.
An Electrician will remove power, disconnect the white timer motor wires, and the screws secuiring it, and replace with same Number on the motor, there are a couple of styles, Need the exact number.
An easy fix, Take notes before dissembly.
Some samples:
http://www.aplussupply.com/intermatic/timermotors.htm

You will have ON trippers and OFF trippers, You can place an ON at Noon, and OFF at 1:00 for 1 hours operation, If you manually turned it back on at 3:00, it would stay on until the next OFF tripper(1:00).
You can have as many ON an OFF trippes as you want.
Intermatic Makes a Timer that is digital and has Battery Backup that keeps time if power is lost?